How deep is the Bee Gees' love of Saturday Night Fever, the Broadway musical inspired by the 1977 movie of the same name? Deep enough that the Brothers Gibb will attend the Oct. 21 opening night of the show (perhaps to remind the audience that they should be dancing).

Barry, Maurice and Robin Gibb make up the Australian-born trio who, after some success as a pop act in the late '60s, reinvented themselves as Disco sensations in the mid-to-late `70s. The film "Saturday Night Fever" is perhaps best known for its propulsive soundtrack, much of it penned and performed by the Bee Gees. Those songs -- "Stayin' Alive," "Night Fever" and "How Deep Is Your Love" -- also inform the stage musical, as do other, non-"SNF" Bee Gees tunes, such as "Tragedy," "Jive Talkin'" and "The Nights on Broadway."

In addition, the Bee Gees wrote a couple new songs for the show, including "It's My Neighborhood."

Also expected to attend opening night is Sarah Ferguson, the former Duchess of York.

Saturday Night Fever began a month of previews Sept. 28. The cast is headed by James Carpinello (Stupid Kids), Paige Price and Orfeh (The Gershwins' Fascinating Rhythm). Also populating the floor at the 2001 Odyssey discotheque are Bryan Batt (as DJ Monty), Paul Castree, Richard H. Blake, Andy Blankenbuehler and Sean Palmer. The film based musical boasts a total cast of 43 and roughly a dozen dance numbers. As it did in London, the musical has already attracted a following, selling over $20 million in tickets, and inspiring screaming, hooting and dancing in the aisles among its largely youngish audiences.

Carpinello wears the dancin' shoes of John Travolta as Bay Ridge boy Tony Manero. Price plays Stephanie, Tony's sassy dance partner and love interest.

For information on Saturday Night Fever call (212) 307-4100.